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It is shown that two types of shape invariance with respect to
quantum numbers \emph{n} and \emph{m} lead us to solve Dirac
equation for a $spin^{-\frac{1}{2}} $charged particle in
two-dimensional and three-dimensional Euclidean spaces in the
presence of magnetic fields. Also, we introduce supersymmetry
algebra and shape invariance symmetry represented by two bunches
of spinors obtained from the above solutions.
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